As northern China choked in lingering smog last month, residents hoped for strong winds to sweep the filth away.
Now they have another reason to wish for a strong breeze: to send potential radiation from North Korea's nuclear test this week away to the southeast.
The Ministry of Environmental Protection said on Wednesday it had increased radiation monitoring in northeastern China following Tuesday's nuclear test and had found no immediate abnormalities. But even if there were any, it said, it would affect only Japan and South Korea.
"The evaluation … based on weather forecasts from the National Meteorological Centre shows that even if radiation is released, it will move southeast, and won't impact China at this stage," the ministry said on Wednesday in a statement accompanied by a diagram showing possible radiation patterns passing across Japan.
Mainland internet users, however, were sceptical.
"Why do I feel so pathetic to be a Chinese?" one microblogger wrote. "There is no sense of security or respect. And [you] have to face endless hurt, humiliation and deceit - all by your own people. The nuclear test is only kilometres away [from Chinese territory]. While the US, Japan and South Korea all said their security was threatened, the ministry said there is nothing to worry about."
Actor Sun Haiying commented: "The statement from Ministry of Environmental Protection definitely represents government, but which one? North Korea?"
The ministry's statement was issued after a rumour that radiation readings had surpassed safety levels in northeastern provinces bordering North Korea spread widely on microblogging services and through text messages on Wednesday.
An editor from the Southern Metropolitan Weekly questioned the environment ministry on his blog, asking why it had moved only in response to increasing public pressure from the public, instead of taking immediate action, and how it could ensure the data it released was accurate.
Some internet users shared links to real-time radiation monitoring networks from Japan and South Korea as references.
Radiation in municipalities and provincial capitals on the mainland were at normal levels at 9am yesterday, the ministry said, adding that it would update radiation data twice a day for Jilin and Liaoning provinces, which border North Korea. Readings for both provinces remained normal yesterday.
Zhang Zhiyong from the China Institute for Radiation Protection, said the impact on the mainland would be limited even if there was some radioactive fallout from the nuclear test.
"Test facilities are usually constructed in regions with a stable geology, so the amount of radioactive particles released into the air is very limited," he said.
He said underground water sources around the test site could be contaminated, but that would not pose a large threat to China because the test happened about 100 kilometres from the border.